The present invention relates to a dental composite carrier, an ampule for prepackaging composite material, and a package which makes possible contamination free storage of the composite and provides for easy handling of the composite.
1. Prior Art
Karter et al, in U.S. Pat. No. 3,735,492 teach a lever type dental amalgam carrier in which the amalgam tips are unitized rapidly interchangeable operating ends, which are adapted to be replaced when a tip becomes defective. While a particular amalgam tip is in use, amalgam is dispensed through the tip by pressing a lever 13 which causes plunger 12 to slide upward along a rod 11.
Hager & Werken catalog, 1984/1985, at page 10, illustrates an amalgam carrier which is used to carry an amalgam after it is prepared, said package comprising a cylindrical well used to hold amalgam, and a plunger which the amalgam carrier uses to force the amalgam out of the package. The amalgam package has threads and the amalgam carrier has a threaded end to which the amalgam package is threaded when used.
2. Background
This invention relates to a composite carrier used for holding and dispensing a polymeric material into a tooth cavity, a composite reservoir which is used with the carrier, and a convenient packaging system for said composite reservoirs. The present invention is particularly adapted for use with light activated composite materials.
Polymeric composites are increasingly gaining acceptance as a substitute for mercury/silver amalgams as a tooth filling material.
In the past, numerous organic compositions have been tried in various mixtures and proportions in order to find a satisfactory composition for use as dental composites or restoratives. These compositions have usually included some type of resin, which may either be preblended or mixed by the practitioner in the office. Dental composite and restorative materials must have good forming characteristics so that they can be shaped to fit a cavity area or molded into place in order to repair chipped or damaged teeth, yet such compositions are generally filled with inorganic materials in order to achieve satisfactory hardness and durability. Consequently, such materials, though moldable, are generally very stiff.
In the case where a preblended composite is provided, the composite is usually packaged in volumes sufficient for multiple uses and the dental practioner is required to either mix two ingredients, when a self cure composite is used, or to remove the composite from the package and use it very quickly, in the case where a light activated composite is used. An approach to this problem is the use of prefilled ampules of the kind represented by, for example, U.S. Pat. No. 4,391,590. The ampules described in the patent are especially useful for lower viscosity materials, but high viscosity materials of the kind used for posterior restorations are not expressed conveniently from such packaging. Since composite materials used as posterior restoratives are desirably very stiff to permit packing and condensing into cavities, special packaging is desirable which provides mechanical means for removing the composite from the package, for example, a bulk syringe, or the package may be provided with a wide opening, such as in a jar, so that the composite can be removed with a spatula. The composite material must then be delivered to the cavity preparation by an amalgam carrier or plastic placement instrument.
These methods of packaging have disadvantages in that when such a stiff material is extruded from bulk packages, it is hard to control the amount of material that is delivered and waste occurs. Also, if the bulk syringe tip becomes clogged, the whole package may have to be discarded.
Similarly, in a package having a large opening, as for example, a jar or tub from which composite is removed with a spatula, extreme care must be taken that the package contents are not contaminated while removing composite from the package. Repeated opening of a jar in a lighted room can also cause premature polymerization of the composite material. Also, when such a package is used, air can be introduced into the package material when a portion is being obtained which results in the introduction of air voids and undesirable porosity.
This method of packaging has the additional disadvantage that the dental technician, after removing the composite from the package, must somehow manipulate the composite onto a carrying device whereby the dentist can deliver the composite effectively to the tooth.
Accordingly, there is a need in the art for an apparatus that provides a convenient, easy, ready to use method of handling a high viscosity composite that is to be used as a dental restorative in incremental portions that are particularly suitable for direct use as a restorative that provides minimum handling of the composite by providing direct access and delivery, and that substantially eliminates the possibility of contamination and prepolymerization of the composite and thereby substantially reduces or eliminates unnecessary waste of material.